Use cargokit for builds and generate Rust->C FFI bindings

LICENSE

@@ -1 +1,16 @@
-TODO: Add your license here.
+Copyright 2025 Cypher Stack LLC
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the “Software”), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial
+portions of the Software.
+
+THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
+OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

README.md

@@ -1,4 +1,10 @@
 # `flutter_libepiccash`
+## Submodules
+Initialize submodules:
+```sh
+git submodule update --init --recursive
+```
+
 ## Dependencies
 ### Rust
 Install Rust: https://www.rust-lang.org/tools/install
@@ -61,10 +67,7 @@ cargo install cbindgen
 ```
 
 ## Build
-```sh
-cd scripts/ios
-./build_all
-```
+Builds are automatically triggered upon a Flutter build using [cargokit](https://github.com/irondash/cargokit) (see [this guide](https://matejknopp.com/post/flutter_plugin_in_rust_with_no_prebuilt_binaries/)).
 
 # Windows
 ## Dependencies
@@ -73,10 +76,18 @@ Run `scripts/windows/deps.sh` in WSL (may need to alter permissions like with `c
 sudo apt-get install clang gcc-mingw-w64-x86-64 g++-mingw-w64-x86-64
 ```
 
-## Building for Windows
-Run `scripts/windows/build_all.sh`
-
-Libraries will be output to `scripts/windows/build`
-
 ## Building on Windows
 `build_all.ps1` is not confirmed working and may need work eg. may need some missing dependencies added but has been included as a starting point or example for Windows users
+
+# Development
+## Cargokit
+Cargokit may be updated using:
+```sh
+git subtree pull --prefix cargokit https://github.com/irondash/cargokit.git main --squash
+```
+in the plugin root.
+
+## Bindings generation
+To generate `epic_cash_wallet.h` C bindings for Rust, `cbindgen --config cbindgen.toml --crate epic_cash_wallet --output target/epic_cash_wallet.h` or `cargo build` in `rust` to produce headers according to `build.rs`.
+
+[//]: # (To generate `epic_cash_bindings_generated.dart` Dart bindings for C, `flutter pub run ffigen --config ffigen.yaml`.)

cargokit/.github/workflows/check_and_lint.yml

@@ -0,0 +1,26 @@
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+name: Check and Lint
+
+jobs:
+  Flutter:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # 4.1.0
+      - uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1 # 2.16.0
+      - name: Pub Get
+        run: dart pub get --no-precompile
+        working-directory: build_tool
+      - name: Dart Format
+        run: dart format . --output=none --set-exit-if-changed
+        working-directory: build_tool
+      - name: Analyze
+        run: dart analyze
+        working-directory: build_tool
+      - name: Test
+        run: flutter test
+        working-directory: build_tool

cargokit/.github/workflows/test_example_plugin_build.yml

@@ -0,0 +1,86 @@
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+name: Test Example Plugin
+
+jobs:
+  Build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - ubuntu-latest
+          - macOS-latest
+          - windows-latest
+        build_mode:
+          - debug
+          - profile
+          - release
+    env:
+      EXAMPLE_DIR: "a b/hello_rust_ffi_plugin/example"
+      CARGOKIT_VERBOSE: 1
+    steps:
+      - name: Extract branch name
+        shell: bash
+        run: echo "branch=${GITHUB_HEAD_REF:-${GITHUB_REF#refs/heads/}}" >> $GITHUB_OUTPUT
+        id: extract_branch
+      - name: Setup Repository
+        shell: bash
+        run: |
+            mkdir "a b" # Space is intentional
+            cd "a b"
+            git config --global user.email "[email protected]"
+            git config --global user.name "Your Name"
+            # "advanced" branch has extra iOS flavor and uses rust nightly for release builds
+            git clone -b advanced https://github.com/irondash/hello_rust_ffi_plugin
+            cd hello_rust_ffi_plugin
+            git subtree pull --prefix cargokit https://github.com/${{ github.event.pull_request.head.repo.full_name || github.repository }} ${{ steps.extract_branch.outputs.branch }} --squash
+      - uses: subosito/flutter-action@44ac965b96f18d999802d4b807e3256d5a3f9fa1 # 2.16.0
+        with:
+          channel: "stable"
+      - name: Install GTK
+        if: (matrix.os == 'ubuntu-latest')
+        run: sudo apt-get update && sudo apt-get install libgtk-3-dev
+      - name: Install ninja-build
+        if: (matrix.os == 'ubuntu-latest')
+        run: sudo apt-get update && sudo apt-get install ninja-build
+      - name: Build Linux (${{ matrix.build_mode }})
+        if: matrix.os == 'ubuntu-latest'
+        shell: bash
+        working-directory: ${{ env.EXAMPLE_DIR }}
+        run: flutter build linux --${{ matrix.build_mode }} -v
+      - name: Build macOS (${{ matrix.build_mode }})
+        if: matrix.os == 'macos-latest'
+        shell: bash
+        working-directory: ${{ env.EXAMPLE_DIR }}
+        run: flutter build macos --${{ matrix.build_mode }} -v
+      - name: Build iOS (${{ matrix.build_mode }})
+        if: matrix.os == 'macos-latest'
+        shell: bash
+        working-directory: ${{ env.EXAMPLE_DIR }}
+        run: flutter build ios --${{ matrix.build_mode }} --no-codesign -v
+      - name: Build iOS (${{ matrix.build_mode }}) - flavor1
+        if: matrix.os == 'macos-latest'
+        shell: bash
+        working-directory: ${{ env.EXAMPLE_DIR }}
+        run: flutter build ios --flavor flavor1 --${{ matrix.build_mode }} --no-codesign -v
+      - name: Build Windows (${{ matrix.build_mode }})
+        if: matrix.os == 'windows-latest'
+        shell: bash
+        working-directory: ${{ env.EXAMPLE_DIR }}
+        run: flutter build windows --${{ matrix.build_mode }} -v
+      - name: Build Android (${{ matrix.build_mode }})
+        shell: bash
+        working-directory: ${{ env.EXAMPLE_DIR }}
+        run: |
+          if [[ $(sysctl hw.optional.arm64) == *"hw.optional.arm64: 1"* ]]; then
+            export JAVA_HOME=$JAVA_HOME_17_arm64
+          else
+            export JAVA_HOME=$JAVA_HOME_11_X64
+          fi
+          flutter build apk --${{ matrix.build_mode }} -v
+

cargokit/.gitignore

@@ -0,0 +1,4 @@
+target
+.dart_tool
+*.iml
+!pubspec.lock

cargokit/LICENSE

@@ -0,0 +1,39 @@
+Copyright 2022 Matej Knopp
+
+================================================================================
+
+MIT LICENSE
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
+OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+================================================================================
+
+APACHE LICENSE, VERSION 2.0
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+

cargokit/README

@@ -0,0 +1,8 @@
+Experimental repository to provide glue for seamlessly integrating cargo build
+with flutter plugins and packages.
+
+See https://matejknopp.com/post/flutter_plugin_in_rust_with_no_prebuilt_binaries/
+for a tutorial on how to use Cargokit.
+
+Example plugin available at https://github.com/irondash/hello_rust_ffi_plugin.
+

cargokit/build_pod.sh

@@ -0,0 +1,58 @@
+#!/bin/sh
+set -e
+
+BASEDIR=$(dirname "$0")
+
+# Workaround for https://github.com/dart-lang/pub/issues/4010
+BASEDIR=$(cd "$BASEDIR" ; pwd -P)
+
+# Remove XCode SDK from path. Otherwise this breaks tool compilation when building iOS project
+NEW_PATH=`echo $PATH | tr ":" "\n" | grep -v "Contents/Developer/" | tr "\n" ":"`
+
+export PATH=${NEW_PATH%?} # remove trailing :
+
+env
+
+# Platform name (macosx, iphoneos, iphonesimulator)
+export CARGOKIT_DARWIN_PLATFORM_NAME=$PLATFORM_NAME
+
+# Arctive architectures (arm64, armv7, x86_64), space separated.
+export CARGOKIT_DARWIN_ARCHS=$ARCHS
+
+# Current build configuration (Debug, Release)
+export CARGOKIT_CONFIGURATION=$CONFIGURATION
+
+# Path to directory containing Cargo.toml.
+export CARGOKIT_MANIFEST_DIR=$PODS_TARGET_SRCROOT/$1
+
+# Temporary directory for build artifacts.
+export CARGOKIT_TARGET_TEMP_DIR=$TARGET_TEMP_DIR
+
+# Output directory for final artifacts.
+export CARGOKIT_OUTPUT_DIR=$PODS_CONFIGURATION_BUILD_DIR/$PRODUCT_NAME
+
+# Directory to store built tool artifacts.
+export CARGOKIT_TOOL_TEMP_DIR=$TARGET_TEMP_DIR/build_tool
+
+# Directory inside root project. Not necessarily the top level directory of root project.
+export CARGOKIT_ROOT_PROJECT_DIR=$SRCROOT
+
+FLUTTER_EXPORT_BUILD_ENVIRONMENT=(
+  "$PODS_ROOT/../Flutter/ephemeral/flutter_export_environment.sh" # macOS
+  "$PODS_ROOT/../Flutter/flutter_export_environment.sh" # iOS
+)
+
+for path in "${FLUTTER_EXPORT_BUILD_ENVIRONMENT[@]}"
+do
+  if [[ -f "$path" ]]; then
+    source "$path"
+  fi
+done
+
+sh "$BASEDIR/run_build_tool.sh" build-pod "$@"
+
+# Make a symlink from built framework to phony file, which will be used as input to
+# build script. This should force rebuild (podspec currently doesn't support alwaysOutOfDate
+# attribute on custom build phase)
+ln -fs "$OBJROOT/XCBuildData/build.db" "${BUILT_PRODUCTS_DIR}/cargokit_phony"
+ln -fs "${BUILT_PRODUCTS_DIR}/${EXECUTABLE_PATH}" "${BUILT_PRODUCTS_DIR}/cargokit_phony_out"

cargokit/build_tool/README.md

@@ -0,0 +1,2 @@
+A sample command-line application with an entrypoint in `bin/`, library code
+in `lib/`, and example unit test in `test/`.

cargokit/build_tool/analysis_options.yaml

@@ -0,0 +1,31 @@
+# This file configures the static analysis results for your project (errors,
+# warnings, and lints).
+#
+# This enables the 'recommended' set of lints from `package:lints`.
+# This set helps identify many issues that may lead to problems when running
+# or consuming Dart code, and enforces writing Dart using a single, idiomatic
+# style and format.
+#
+# If you want a smaller set of lints you can change this to specify
+# 'package:lints/core.yaml'. These are just the most critical lints
+# (the recommended set includes the core lints).
+# The core lints are also what is used by pub.dev for scoring packages.
+
+include: package:lints/recommended.yaml
+
+# Uncomment the following section to specify additional rules.
+
+linter:
+  rules:
+    - prefer_relative_imports
+    - directives_ordering
+
+# analyzer:
+#   exclude:
+#     - path/to/excluded/files/**
+
+# For more information about the core and recommended set of lints, see
+# https://dart.dev/go/core-lints
+
+# For additional information about configuring this file, see
+# https://dart.dev/guides/language/analysis-options

cargokit/build_tool/bin/build_tool.dart

@@ -0,0 +1,5 @@
+import 'package:build_tool/build_tool.dart' as build_tool;
+
+void main(List<String> arguments) {
+  build_tool.runMain(arguments);
+}

cargokit/build_tool/lib/build_tool.dart

@@ -0,0 +1,5 @@
+import 'src/build_tool.dart' as build_tool;
+
+Future<void> runMain(List<String> args) async {
+  return build_tool.runMain(args);
+}